For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningInstallation Procedure
Drill 8 mm (5/16 in) for plug welding along the edges of the service
panel as noted from the original
panel.
Clean and prepare the attaching surfaces for welding.
Position the body lock pillar inner panel on the vehicle.
Verify the fit of the panel.
Clamp th ...
Installation Procedure
Install the following components on the drivetrain and front suspension
frame if removed:
The radiator support brackets.
The stabilizer shaft--Refer to Stabilizer Shaft Replacement.
The lower control arms--Refer to Lower Control Arm Replacement.
The steering gear--Refer to Steering ...
Hazard Warning Flashers
(Hazard Warning Flasher):
Press and momentarily hold this button on the instrument panel above the climate
control system, to make the front and rear turn signal lamps flash on and off. This
warns others that you are having trouble.
Press and momentarily hold again to turn the flashers off ...